Total body fat and its distribution are related to the development of non-insulin dependent diabetes mellitus (NIDDM). It is unknown whether insulin sensitivity is correlated more closely to intra-abdominal, subcutaneous, total, or other regional fat in postmenopausal women. We measured intra-abdominal fat (IAF), subcutaneous fat (SQF), and sagittal diameter (SD) at the L4-L5 vertebral disc space with computed tomography (CT); total body fat (TBF), % fat (PF), arm fat (AF), leg fat (LF), and trunk fat (TF) using dual photon x-ray absorptiometry (DEXA); and insulin sensitivity (M) using euglycemic clamps in 27 non-diabetic early postmenopausal women, ages 50.814/1 years, who were not taking hormone replacement. The means and standard deviations were: IAF= 88.1132.7 cm2, SQF=270.3186.4 cm2, SD=214.4 cm, TBF= 22.717.0 kg, PF=34.615.9%, AF=2.410.9 kg, LF=8.512.7 kg, TF=10.31 3.5 kg, and M= 449.71119.5 mg/min. M correlated more strongly with SQF (r= -0.39, p= 0.04) and SD (r= -0.42, p=0.02), than to IAF (r=-0.32, p=0.11), TBF (r= -0.26, p=0.19), PF (r=-0.20, 0.31), AF (r= -0.15, p=.44), LF (r= -0.22, p=0.28), or TF (r= 0.32, p= 0.10). We conclude that abdominal SQF and SD are most highly correlated to insulin sensitivity in postmenopausal women. Efforts to reduce SQF should be most helpful in reducing the risk of NIDDM in postmenopausal women. Ongoing studies will determine if hormone replacement therapy affects body fat compartments and insulin sensitivity in these women.